Magma volcanic eruption

Volcanism Volcanic eruptions during which magma from the mantle is extruded into or onto Earth s crust. Once the magma has escaped from the mantle, it is termed lava. 

A long-standing geochemical problem is the source of water in volcanic eruptions and geothermal systems how much is derived from the magma itself and how much is recycled meteoric water One of the principal and unequivocal conclusions drawn from stable isotope studies of fluids in volcanic hydrothermal systems is that most hot spring waters are meteoric waters derived from local precipitation (Craig et al. 1956 Clayton et al. 1968 Clayton and Steiner 1975 Truesdell and Hulston 1980, and others). 

The third and the most common type is complex phase transformations, including the following (i) some components in a phase combine to form a new phase (e.g., H2O exsolution from a magma to drive a volcanic eruption the precipitation of calcite from an aqueous solution, Ca + + COf calcite the condensation of corundum from solar nebular gas and the crystallization of olivine from a basaltic magma), (ii) one phase decomposes into several phases (e.g., spinodal decomposition, or albite jadeite + quartz), (iii) several phases combine into one phase (e.g., melting at the eutectic point, or jadeite +... 

Simple Phase Transition Aragonite to Calcite Complex Phase Transformation Complex Phase Transformation Magma to Rock Volcanic Eruption ... 

Dynamics of explosive volcanic eruptions are in many aspects similar to beer and champagne dynamics. They are driven by the exsolution of a gas from a liquid. Figure 4-31 describes the various stages of an explosive eruption. In the magma chamber, much H2O (such as 6 wt%) and some CO2 (such as 40 ppm) are... 

Dingwell D. (1998) Recent experimental progress in the physical description of silicic magma relevant to explosive volcanism. In The Physics of Explosive Volcanic Eruptions. Geology Society of Lxtndon Special Publication 145 (eds. J. S. Gilbert and R. S. J. Sparks). Geological Society of Lxtndon, pp. 9-26. 

Macdonald K. C. and Fox P. J. (1988) The axial summit graben and cross-sectional shape of the East Pacific Rise as indicators of axial magma chambers and recent volcanic eruptions. Earth Planet. Sci. Lett. 88, 119-131. 

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